1. Field of the Disclosure
This disclosure relates in general to aqueous dispersions of electrically conductive polymers containing solvent and additives, and their use in electronic devices.
2. Description of the Related Art
Electronic devices define a category of products that include an active layer. Organic electronic devices have at least one organic active layer. Such devices convert electrical energy into radiation such as light emitting diodes, detect signals through electronic processes, convert radiation into electrical energy, such as photovoltaic cells, or include one or more organic semiconductor layers.
Organic light-emitting diodes (OLEDs) are an organic electronic device comprising an organic layer capable of electroluminescence. OLEDs containing conducting polymers can have the following configuration:                anode/hole injection layer/EL material/cathodewith additional layers between the electrodes. The anode is typically any material that has the ability to inject holes into the EL material, such as, for example, indium/tin oxide (ITO). The anode is optionally supported on a glass or plastic substrate. EL materials include fluorescent compounds, fluorescent and phosphorescent metal complexes, conjugated polymers, and mixtures thereof. The cathode is typically any material (such as, e.g., Ca or Ba) that has the ability to inject electrons into the EL material. Electrically conducting polymers having low conductivity in the range of 10−3 to 10−7 S/cm are commonly used as the hole injection layer in direct contact with an electrically conductive, inorganic oxide anode such as ITO.        
Electrically conducting polymers which have the ability to carry a high current when subjected to a low electrical voltage, may have utility as electrodes for electronic devices. However, many conductive polymers have conductivities which are too low for use as electrodes such as the anode for OLEDs. Moreover, they generally have a work-function that is too low for effective hole injection as an anode. Having high conductivity and high work-function is also useful as cathode, for example, in Tantalum/Ta2O5 or Aluminum/Al2O3 capacitors. Furthermore, the mechanical strength of films made from the polymers, either self-standing or on a substrate, may not be sufficient for the electrode applications. In addition, the refractive index of these materials is generally low.
Accordingly, there is a continuing need for improved organic conductive materials.